WATERTOWN, Mass.--(BUSINESS WIRE)--May 8, 2017--
Seventh paragraph, second sentence of release dated May 8, 2017, should
read: “For the six months ended March 31, 2017, net loss was $10.4
million, or ($0.54) per diluted common share, compared to net income of
$24.5 million, or $1.28 per diluted common share...” (instead of $1.28
million per diluted common share).

R&D expense increased to $13.0 million in support of pipeline
development

Cash and marketable securities totaled $240.9 million at March
31, 2017

Enanta Pharmaceuticals, Inc. (NASDAQ:ENTA), a research and
development-focused biotechnology company dedicated to creating small
molecule drugs for viral infections and liver diseases, today reported
financial results for its fiscal second quarter ended March 31, 2017.

Enanta’s cash, cash equivalents and short-term and long-term marketable
securities totaled $240.9 million at March 31, 2017. This compares to a
total of $242.2 million in such accounts at September 30, 2016. Enanta
expects that its current cash, cash equivalents and marketable
securities will be sufficient to meet the anticipated cash requirements
of its existing business and development programs for the foreseeable
future.

Fiscal Second Quarter Ended March 31, 2017 Financial Results

Total revenue for the three months ended March 31, 2017 was $9.0
million, compared to $13.0 million for the three months ended March 31,
2016. For the six months ended March 31, 2017, total revenue was $19.4
million, compared to $61.4 million for the same period in 2016. For the
three and six month periods ended March 31 2017, revenue consisted
exclusively of royalties earned on AbbVie’s worldwide net sales of HCV
regimens containing paritaprevir. For the 2016 six month period, revenue
consisted primarily of royalty revenues as well as a $30.0 million
milestone payment for the reimbursement approval of VIEKIRAX® in Japan.
Milestone payments and royalties have varied significantly from period
to period, and we expect that variability to continue in the future.

Research and development expenses totaled $13.0 million for the three
months ended March 31, 2017, compared to $9.1 million for the three
months ended March 31, 2016. For the six months ended March 31, 2017,
research and development expenses totaled $25.5 million compared to
$18.2 million for the same period in 2016. The increase in research and
development expenses was primarily due to increased preclinical and
clinical costs associated with the progression of Enanta’s wholly-owned
R&D programs in non-alcoholic steatohepatitis (NASH)/primary biliary
cholangitis (PBC), respiratory syncytial virus (RSV) and hepatitis B
virus (HBV).

General and administrative expenses totaled $5.5 million for the three
months ended March 31, 2017, compared to $4.4 million for the three
months ended March 31, 2016. For the six months ended March 31, 2017,
general and administrative expenses was $10.4 million, compared to $8.2
million for the same period in 2016. For the three month period, the
increase in general and administrative expenses was primarily due to
increases in stock-based compensation expense driven by increased
headcount. For the six month period, the increase was due to increased
headcount as well as achievement of milestones under existing
performance-based stock awards.

Enanta recorded an income tax benefit for the three months ended March
31, 2017 of $3.6 million compared to an income tax expense of $1.6
million for the same period in 2016. The Company’s estimated annual
effective tax rate for fiscal 2017 of 33.0 percent was slightly below
the statutory rate of 35.0 percent due to the availability of federal
research and development tax credits.

Net loss for the three months ended March 31, 2017 was $5.4 million, or
$(0.28) per diluted common share, compared to net loss of $1.6 million,
or ($0.09) per diluted common share, for the corresponding period in
2016. For the six months ended March 31, 2017, net loss was $10.4
million, or ($0.54) per diluted common share, compared to net income of
$24.5 million, or $1.28 per diluted common share, for the corresponding
period in 2016.

“With our second partnered protease inhibitor product, glecaprevir,
expected to launch starting in August as part of AbbVie’s new,
investigational G/P treatment for HCV, the prospects for additional
milestone and royalty payments to us for G/P are significant,” stated
Jay R. Luly, Ph.D., President and Chief Executive Officer, Enanta. “Any
such payments, coupled with our existing financial resources, will allow
us to advance our clinical program in NASH/PBC and also fund our
additional R&D programs, including our lead compound EDP-938 for RSV,
scheduled to begin clinical development later this year.”

Development Program and Business Review

Enanta presented new preclinical data on EDP-305, its wholly-owned FXR
agonist for non-alcoholic steatohepatitis, at the International Liver
Congress™ (ILC) 2017 in Amsterdam. Data from three poster
presentations presented at the Congress demonstrated that EDP-305 is a
potent Farnesoid X receptor (FXR) agonist that has been shown to
reduce expression of fibrogenic genes, reduce fibrosis progression and
improve non-alcoholic fatty liver disease (NAFLD) activity scores
(NAS) in a variety of preclinical models.

Enanta expects to present clinical data from our ongoing Phase 1
clinical study of EDP-305 in healthy volunteers and presumed NAFLD
subjects1 and to initiate NASH-enabling studies in the
second half of this year. A Phase 2 study in PBC is expected to begin
in the fourth quarter of calendar 2017 and Phase 2 studies in NASH are
expected to begin in early 2018.

Also at the ILC, AbbVie presented new data from its investigational,
pan-genotypic, ribavirin-free regimen for hepatitis C virus (HCV)
consisting of a combination of glecaprevir/pibrentasvir (G/P). Data
from the EXPEDITION-1 study demonstrated that 99 percent (n=145/146)
of chronic HCV infected patients with genotype 1, 2, 4, 5 or 6 and
compensated cirrhosis (Child-Pugh A) achieved sustained virologic
response at 12 weeks post-treatment (SVR12) with G/P. This
high SVR12 rate was seen following 12 weeks of G/P
treatment without ribavirin. Data were also presented at the ILC from
the ENDURANCE-3 study. In this study, 95 percent (n=149/157) of
genotype 3 (GT3) chronic HCV-infected patients without cirrhosis and
who were new to treatment, achieved sustained virologic response at 12
weeks post-treatment (SVR12) following 8 weeks of treatment
with G/P.

In March, Enanta announced the Japanese Ministry of Health, Labour and
Welfare (MHLW) granted priority review designation to AbbVie’s G/P
combination for the treatment of all major genotypes (GT1-6) of
chronic hepatitis C virus (HCV) infection. AbbVie had submitted the
NDA for the G/P regimen in Japan in February 2017. The NDAs for G/P in
the U.S and Japan have been granted priority review designation, and
the MAA for G/P has been granted accelerated assessment in the E.U.

Upcoming Events and Presentations

On June 25 at the XIX International Symposium on Respiratory Viral
Infections in Berlin, Germany, Enanta will present data on EDP-938, its
respiratory syncytial virus inhibitor candidate in an oral presentation
titled: “EDP-938, a Novel Non-Fusion Replication Inhibitor of
Respiratory Syncytial Virus, Demonstrates Potent Antiviral Activities
both In Vitro and In Vivo”.

Enanta plans to issue its fiscal third quarter financial results press
release, and hold a conference call regarding those results, on August
7, 2017.

Conference Call and Webcast InformationEnanta will host a
conference call and webcast today at 4:30 p.m. Eastern time. To
participate in the live conference call, please dial (855) 840-0595 in
the U.S. or (518) 444-4814 for international callers. A replay of the
conference call will be available starting at approximately 7:30 p.m.
Eastern time on May 8, 2017, through 11:59 p.m. Eastern time on May 12,
2017 by dialing (855) 859-2056 from the U.S. or (404) 537-3406 for
international callers. The passcode for both the live call and the
replay is 6851190. A live audio webcast of the call and replay can be
accessed by visiting the “Calendar of Events” section on the “Investors”
page of Enanta’s website at www.enanta.com.

About EnantaEnanta Pharmaceuticals is a research and
development-focused biotechnology company that uses its robust
chemistry-driven approach and drug discovery capabilities to create
small molecule drugs for viral infections and liver diseases. Enanta’s
research and development efforts are currently focused on the following
disease targets: non-alcoholic steatohepatitis (NASH)/ primary biliary
cholangitis (PBC), respiratory syncytial virus (RSV) and hepatitis B
virus (HBV).

Enanta has discovered novel protease inhibitors for use against the
hepatitis C virus (HCV). These protease inhibitors, developed through
Enanta’s collaboration with AbbVie, include paritaprevir, currently
marketed in AbbVie’s HCV regimens, and glecaprevir (ABT-493), Enanta’s
second protease inhibitor product, which AbbVie is developing as part of
its investigational, pan-genotypic HCV regimen of
glecaprevir/pibrentasvir (G/P) now in registration in the U.S., the E.U.
and Japan and other jurisdictions. Royalties and any further milestone
payments from this collaboration will provide additional funding for
Enanta’s earlier development programs, including its Phase 1 FXR agonist
program for NASH/PBC, and its preclinical programs for HBV and RSV.
Please visit www.enanta.com
for more information on Enanta’s programs and pipeline.

Forward Looking StatementsThis press release contains
forward-looking statements, including statements with respect to the
prospects for AbbVie’s investigational G/P regimen in HCV and the
prospects for advancement of Enanta’s earlier stage programs in NASH/PBC
and RSV. Statements that are not historical facts are based on
management’s current expectations, estimates, forecasts and projections
about Enanta’s business and the industry in which it operates and
management’s beliefs and assumptions. The statements contained in this
release are not guarantees of future performance and involve certain
risks, uncertainties and assumptions, which are difficult to predict.
Therefore, actual outcomes and results may differ materially from what
is expressed in such forward-looking statements. Important factors and
risks that may affect actual results include: Enanta’s revenues in the
short-term are dependent upon the success of AbbVie’s continuing
commercialization efforts for its HCV treatment regimens containing
paritaprevir; Enanta’s longer-term revenues will be dependent upon the
success of AbbVie’s efforts to obtain regulatory approvals for G/P and
commercialize that regimen; competitive pricing, market acceptance and
reimbursement rates of AbbVie’s treatment regimens containing
paritaprevir or its G/P combination compared to competitive HCV products
on the market and product candidates of other companies under
development; the discovery and development risks of early stage
discovery efforts in other disease areas such as NASH, PBC,RSV and HBV;
potential competition from the development efforts of others in those
other disease areas; Enanta’s lack of clinical development experience;
Enanta’s need to attract and retain senior management and key scientific
personnel; Enanta’s need to obtain and maintain patent protection for
its product candidates and avoid potential infringement of the
intellectual property rights of others; and other risk factors described
or referred to in “Risk Factors” in Enanta’s most recent Form 10-K for
the fiscal year ended September 30, 2016 and other periodic reports
filed more recently with the Securities and Exchange Commission. Enanta
cautions investors not to place undue reliance on the forward-looking
statements contained in this release. These statements speak only as of
the date of this release, and Enanta undertakes no obligation to update
or revise these statements, except as may be required by law.

1 Presumed NAFLD subjects in this study are obese subjects,
with or without pre-diabetes or type-2 diabetes.